Preparation and application of polyolefins have been rapidly developed with a development of a catalyst called a Ziegler-Natta catalyst, and a variety of production processes and applications of the products have been also developed. Recently, metallocene catalysts have been commonly used in the preparation of polyolefins, and metallocene catalysts discovered by kaminsky's group in 1980 are composed of a transition metal as a main catalyst and an organic aluminium compound as a co-catalyst. The metallocene catalyst is a homogeneous complex catalyst having a single active site, and produces polymers with a narrow molecular weight distribution and a uniform comonomer distribution according to the single-site characteristics. In addition, the metallocene catalyst has the properties of controlling the stereoregularity, copolymerization characteristics, molecular weight, crystallinity, and so forth of the obtained polymer by changing the ligand structure of the catalyst and the polymerization conditions.
Meanwhile, there have been attempts to apply an olefin-based polymer prepared by using the metallocene catalyst to hot-melt adhesive (HMA), and the hot-melt adhesive is required to exhibit superior melt processability and superior adhesive properties at low temperature. However, since most of the previously known olefin-based polymers did not satisfy both of the melt processability and the adhesive properties, there has been a limit in their application to the hot-melt adhesive.